The concept of generating silica from alkoxysilanes by the sol-gel method within a macromolecular organic phase (in situ) is widely known in the art. The organic and inorganic components of these materials are present as co-continuous phases of a few nanometers in lateral dimensions (Leno Mascia, R J. Heath, and Vincent S. Y. Ng, “Selective Repartition of In Situ Generated Silica Produced During the Evolution of an Epoxide Network from a Homogeneous Precursors Mixture and Effects on Properties.” Journal of Applied Polymer Science, 2004, Vol. 94, No. 3, pp. 1279 to 1290).
The synthesis of epoxy amine sol-gel organic-inorganic materials is sufficiently flexible to allow fabrication of a wide group of hybrids with different structures and properties, whose applications range from non-linear optics to adhesive and protective coatings (P. Innocenzi, T. Kidchob, and T. Yoko, “Hybrid Organic-Inorganic Sol-Gel Materials Based on Epoxy-Amine Systems.” Journal of Sol-Gel Science and Technology, 2005, Vol. 35, No. 3, pp. 225 to 235).
Oligomer compositions that contain a mixture of certain alkylalkoxysilanes with amine and epoxy end groups are well known in the art. For example, U.S. Pat. No. 3,837,876 issued to Mayuzumi, et al. in 1974 describes compositions for adhesion purposes, which consist essentially of the reaction product of epoxyalkylalkoxysilane with aminoalkylalkoxysilane. Organosilicone compositions are used in the form of a blend with a sealant or a primer coating for improving the adhesion of such blends onto various surfaces or for adhesion of the sealant, itself, onto various surfaces, respectively.
A transparent and scratch-resistant coating composition that comprises a partially hydrolyzed carbon-functional silane derived from aminoalkylalkoxysilane and epoxyalkylalkoxysilane is described in U.S. Pat. No. 3,961,977 issued to H. Koda, et al, in 1976.
U.S. Pat. No. 4,791,214 issued to Mori, et al, in 1988 describes a bonding agent that comprises a reaction product or mixture of epoxyalkylalkoxysilane and polyamine in an approximately stoichiometrically equivalent amount. The bonding agent is used preferably as an essentially non-reactive additive to various resin compositions in an amount of 0.1 to 20 parts by weight (as solid) to 100 parts by weight of the resin composition in order to impart excellent adhesion to the resin composition, particularly excellent durability of adhesion. Synthetic resins used as the main ingredient of the resin composition include conventional polyester resins, epoxy resins, alkyd resins, amino-alkyd resins, and the like, and type of synthetic rubber include conventional polyurethane rubber, silicone rubber, polysulfide rubber, and the like.
U.S. Pat. No. 5,173,206 issued to Dickens, et al, in 1992 relates to an oxidation-resistant composition that is a binary or a ternary composition made from at least one amino-containing silane compound, such as aminosilane or polyaminosilane, or from at least one epoxy resin, epoxy silane compound, or all three such compounds.
U.S. Pat. No. 5,314,980 issued to Morrison in 1994 relates to a coating composition that comprises epoxy silane, an amine hardener that can react with epoxy silane to form a cross-linked coating, and a stabilizer that includes a sufficient amount of a metal component to delay cross-linking between the epoxy silane and the amine hardener.
U.S. Pat. No. 6,713,586 issued to Greene in 2004 describes an epoxy-functional organopolysiloxane coating composition that comprises epoxy-functional organopolysiloxane resin and a hardener. The epoxy-functional organopolysiloxane coating composition may optionally include pigments, a flow additive, and a catalyst. The epoxy-functional organopolysiloxane resin is preferably prepared by reacting silicone resin with a silane having at least one epoxy group per molecule. The coating composition cures through the crosslinking of epoxy groups of the resin to provide a coating that is weather- and corrosion resistant. The polysiloxane moieties in the resin render the cured coating resistant to both ultraviolet light and heat.
U.S. Pat. No. 42,500,074 issued to Foscante, et al, in 1981 relates to polymeric structures having interpenetrating matrices in a cured form, comprising an epoxy-polyamine network and a polysiloxane network. The physical and chemical properties of the interpenetrating network are improved over those of either polymeric component alone. The network can be prepared by simultaneously reacting epoxy resin having at least two oxirane groups with an amine curing agent, and having at least 0.1 equivalent of silane, water being substantially and uniformly distributed throughout the mixture in an amount sufficient to bring about substantial hydrolytic polycondensation of the silane to form a cross-linked interpenetrating polymer network. The amine-curing agent may be substituted wholly or in part with aminosilane. Sources of silane may include aminosilane and epoxysilane.
U.S. Pat. No. 5,618,860 issued to Mowrer, et al, in 1997 relates to a sprayable, trowelable epoxy-polysiloxane-based coating and flooring composition that exhibits excellent weatherability in sunlight and superior resistance to chemicals, corrosion, and impact after curing and that comprises the following: (a) a resin component that includes a non-aromatic epoxy resin having at least two 1,2-epoxy groups per molecule; polysiloxane, and organooxysilane; (b) a difunctional aminosilane hardener component; (c) an organotin catalyst; and (d) an aggregate or pigment component. Organic solvents and flow-modifying agents can be added to facilitate spray application. The resin component, hardener component, aggregate component, and desired catalysts are combined in the presence of a sufficient amount of water to promote the hydrolysis of polysiloxane and/or organooxysilane and the polycondensation of silanols produced by such hydrolysis. Aminosilane and epoxide resin react to form a cured linear epoxy polymer. Polysiloxane and/or organooxysilane undergo a hydrolysis reaction that produces silanol. Silanol undergoes polycondensation, thereby forming a linear epoxy-modified polysiloxane polymer.
U.S. Pat. No. 5,804,616 issued to Mowrer, et al, in 1998 describes an epoxy-polysiloxane polymer composition prepared by combining a resin component with a hardener component. The resin component comprises a non-aromatic epoxy-resin ingredient and a polysiloxane ingredient. The hardener component comprises amine and, optionally, an organotin catalyst. The composition can also include aggregates, pigments, and other additives, depending on the particular end use. The composition is prepared using a sufficient amount of water to promote hydrolysis of the polysiloxane and polycondensation of the silanols produced by such hydrolysis. In its cured form, the epoxy-polysiloxane composition exists as a uniformly dispersed arrangement of linear epoxy-chain fragments that are cross-linked with a continuous polysiloxane polymer chain, thereby forming a non-interpenetrating polymer network chemical structure that has substantial advantages over conventional epoxy systems. Protective coatings formed from such compositions exhibit excellent weatherability in sunlight and superior chemical and corrosion resistance after curing.
U.S. Pat. No. 5,942,073 issued to Mowrer, et al, in 1999 relates to an adhesive system that comprises a siloxane-modified adhesive component. The siloxane-modified adhesive component is prepared by combining epoxy resin with an organosilane ingredient, polysiloxane resin, amine hardener, organometallic catalyst, base catalyst, and any thickener and extender pigment.
U.S. Pat. No. 7,459,515 issued to Gommans, et al, in 2008 relates to fast-curing modified siloxane compositions that comprise the following: (1) an alkoxy- or silanol-functional silicone intermediate, (2) at least one amine-reactive ingredient selected from the group consisting of acetoacetate-functional ingredients, acrylate-functional ingredients, and mixtures thereof, (3) an epoxy-functional ingredient, (4) a curing agent selected from the group consisting of amines, aminosilanes, ketimines, aldimines and mixtures thereof, and (5) water. Other ingredients useful in forming fast-curing modified siloxane compositions of this invention include silanes, organometallic catalysts, solvents, pigments, fillers, and modifying agents. The above-identified ingredients are combined and react to form a fully cured protective film comprising a cross-linked enamine polysiloxane and/or an acrylate polysiloxane chemical structure in a reduced amount of time when compared with conventional epoxy siloxane compositions.
The so-formed epoxy polysiloxane composition provides improved properties of weatherability and chemical and corrosion resistance when compared with conventional nonsiloxane-containing epoxy resin compositions. While this epoxy siloxane coating composition provides improved performance properties, similar to the epoxy siloxane composition discussed above (U.S. Pat. Nos. 42,500,074, 5,618,860, 5,804,616, and 5,942,073), this composition is known to be somewhat brittle and therefore lacking the desired degree of impact, flexibility, and abrasion resistance for certain applications.
Therefore, it is desired that an epoxy siloxane composition be developed that is both capable of providing the desired properties of weatherability and corrosion and chemical resistance already associated with epoxy siloxane compositions, while also providing improved properties of impact flexibility, and abrasion resistance.
Also, in all cases described above, the compositions include mixtures of epoxy resins, amine hardeners, and functional silanes and/or polysiloxanes in the presence of water and in an amount sufficient to bring about substantial hydrolytic polycondensation of the silane.
Well known in the art are products of reactions of aminoalkyl alkoxyalkylsilanes and cyclic carbonates as intermediate for conventional polyurethanes production.
U.S. Pat. No. 5,001,210 issued to Coury, et al, in 1991 provides a method for producing polyurethane that incorporates a polydimethylsiloxane backbone. The method consists of reacting amino-terminated polydimethylsiloxane with a cyclic carbonate to produce urethane diol and reacting the urethane diol produced in the previous step with one or more diisocyanates or polyisocyanates to produce polyurethane.
U.S. Patent Application Publications No. 2004/0077778 published in 2004 (Hazan, et al), No. 2005/0208312 published in 2005 (Hazan, et al), and No. 2006/0115611 published in 2006 (Hazan, et al) describe a one-pack primer sealer composition containing a film-forming binder. The composition comprises (a) a silane-functional oligomer with a hydrolyzable group and an additional urethane group formed by first reacting an aminosilane monomer with a cyclic carbonate and then subsequently reacting the adduct formed with isocyanate or polyisocyanate; (b) a low-molecular-weight polyol compound or polymer; (c) a silane-coupling agent; and (c) a melamine formaldehyde crosslinking agent.
Also, it is well known to obtain nanocompositions with the help of nanofillers. U.S. Patent Application Publication No. 2007/0135588 published in 2007 (Diakoumakos, et al) describes quickly curable non-isocyanate-based polyurethane and polyurethane-epoxy network nanocomposite polymeric compositions comprising natural or modified nano-clay with either a monomer or oligomer bearing at least one cyclocarbonate group or a mixture of the latter with epoxy resin and a hardener, which is a monomer or oligomer, or mixtures thereof, bearing primary and/or secondary amino groups. However, nanosize fillers are very expensive. Also, their embedding into liquid oligomer compositions presents substantial technological difficulties.